diff options
| author | Daniel Borkmann <daniel@iogearbox.net> | 2018-01-26 23:33:40 +0100 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2018-01-27 01:42:06 +0100 |
| commit | 3e5b1a39d7cfaa3c023c17f5d12b3f22af046929 (patch) | |
| tree | f139834adf49f268f427600ae01ec1ab662baff8 /arch/x86/net | |
| parent | bpf: fix subprog verifier bypass by div/mod by 0 exception (diff) | |
| download | linux-3e5b1a39d7cfaa3c023c17f5d12b3f22af046929.tar.xz linux-3e5b1a39d7cfaa3c023c17f5d12b3f22af046929.zip | |
bpf, x86_64: remove obsolete exception handling from div/mod
Since we've changed div/mod exception handling for src_reg in
eBPF verifier itself, remove the leftovers from x86_64 JIT.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'arch/x86/net')
| -rw-r--r-- | arch/x86/net/bpf_jit_comp.c | 20 |
1 files changed, 0 insertions, 20 deletions
diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index 5acee5139e28..4923d92f918d 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -568,26 +568,6 @@ static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image, */ EMIT2(0x31, 0xd2); - if (BPF_SRC(insn->code) == BPF_X) { - /* if (src_reg == 0) return 0 */ - - /* cmp r11, 0 */ - EMIT4(0x49, 0x83, 0xFB, 0x00); - - /* jne .+9 (skip over pop, pop, xor and jmp) */ - EMIT2(X86_JNE, 1 + 1 + 2 + 5); - EMIT1(0x5A); /* pop rdx */ - EMIT1(0x58); /* pop rax */ - EMIT2(0x31, 0xc0); /* xor eax, eax */ - - /* jmp cleanup_addr - * addrs[i] - 11, because there are 11 bytes - * after this insn: div, mov, pop, pop, mov - */ - jmp_offset = ctx->cleanup_addr - (addrs[i] - 11); - EMIT1_off32(0xE9, jmp_offset); - } - if (BPF_CLASS(insn->code) == BPF_ALU64) /* div r11 */ EMIT3(0x49, 0xF7, 0xF3); |